932 INFLAMMATION OF THE HIP-JOINT. 



extend the limb, it becomes necessary to use mechanical aids. Ex- 

 tension once effected, it remains for the operator to effect reposition. 

 This may sometimes be done by abduction, sometimes by adduction 

 and rotation of the limb, though, as a rule, the latter is impossible 

 of accomplishment. In Ranson's case the procedure was to place 

 a thiek. round piece of wood between the horse's thighs, thrusting 

 it up as near the pubic region as possible, and by pressing strongly 

 on the tibia to convert the limb into a lever of the first order, and 

 so raise the displaced head of the femur. The operator, with his 

 hand on the head of the bone, then directed the limb to be moved 

 backwards or forwards with the object of bringing the head over 

 the cotyloid cavity. In Ranson's case a sharp movement, accom- 

 panied by a loud " click," announced the return of the head to its 

 proper position. The animal at once regained control of the limb. 

 In smaller animals, like dogs, extension and counter-extension may 

 be left to an assistant, whilst the operator, having taken note of the 

 abnormal position of the caput femoris, effects reposition. 



After successful replacement, the horse should be slung to prevent 

 it lying down, which might cause a relapse. Prolonged rest is 

 absolutely necessary in all animals. 



IV.— INFLAMMATION OF THE HIP JOINT (COXITIS). 



With the exception of the elbow-joint, the coxo-femoral articu- 

 lation seems least of all subject to disease processes, and in horses 

 is seldom affected, though in them, and still more frequently in 

 cattle, displacement, accompanied by partial or total rupture of 

 the ligamentum teres and of the capsular ligament does occur. In 

 some of Harms' collected cases (cattle) the head of the femur showed 

 abraded spots. Eberhardt also reports cases in cattle where the 

 post-mortem showed rupture of the ligamentum teres and of certain 

 muscles around the hip -joint. 



Contusion of the hip-joint follows falls on rough, hard ground, 

 though the bursa of the gluteus medius is then more apt to become 

 inflamed. 



Spontaneous inflammation of the hip-joint is a rarity. In oxen 

 double-sided purulent coxitis was seen by Noak, probably from 

 embolism following traumatic pericarditis. In navel-disease in foals, 

 purulent inflammation of the joint sometimes develops. In cattle, 

 as in men, some cases of suppuration in the hip-joint are due to 

 tuberculosis. 



The chronic inflammation termed malum coxa? senile, so common 



